Wine production began in California with Spanish missionaries producing sacramental wine. The ensuing 1849 California gold rush resulted in the production of wine for commercial purposes, and the planting of vineyards increased, particularly around the regions of Sonoma, Napa and Santa Clara.
By the end of the 1800s, California was producing 1.1 million hectare litres a year (1.5 million bottles). However, by 1919, the Volstead Act banning the production, transport, and sale of wine – known as prohibition -- almost completely destroyed the budding wine industry.
Production plummeted over 93 per cent from 200 million cases in 1918 to 13 million in 1925. Ironically, alcohol consumption doubled from 60 million to 150 gallons due to families making wine at home. Prohibition was repealed in 1933 and California winemakers struggled to get back on their feet through the Second World War, but in the 1970s the wine industry saw a burst of investment.
California has created its own regulatory system, known as the AVA, or American Viticultural Area, which is defined by geographic and climatic boundaries. However, unlike France's AOC laws there are no restrictions on yields, planting varieties or practices like irrigation.
As a result, Californian winemakers are free to plant what they like and can experiment with different winemaking techniques. There is also no legal definition of the word ‘Reserve’ on a label and thus this word can mean something different depending on the producer, from ageing in oak to being the top wine amongst a range.
California has an excellent climate for making wine: Napa Valley has an average annual temperature of 57.7 degrees Fahrenheit (14 degrees Centigrade) with over 2,000 hours of sunshine a year.
While California accounts for 90 per cent of US wine production, or 189 million cases a year, making it the 4th largest producer of wine in the world, Napa Valley accounts for only 5 per cent of California’s wine production. Some of the top Cabernets, known as ‘Cult California wines’ include Screaming Eagle, Schrader, Colgin, and Harlan.
To the west of Napa Valley is Sonoma Valley, which has a cooler climate than Napa particularly in the north where it is closer to the ocean and not protected by the mountain ranges. As such, it is best known for cool-climate grapes such as Pinot Noir and Chardonnay; while Napa is the Bordeaux of California, Sonoma is the Burgundy with regards to grape varietals grown and climates.
To the south, the best known wine region is Paso Robles and Santa Barbara County, made famous is the 2004 sleeper film, ‘Sideways’. The cult California wine, Sine Qua Non, hails from Ventura, just south of Santa Barbara County. True to California’s open approach to wine making, all varieties from Chardonnay to Cabernet are planted in Southern California, but the area is particularly well-known for its Rhone varietals: Grenache, Syrah, and Mourvedre.
While wines from Burgundy and Bordeaux are some of the most expensive wines in the world, California has its fair share of collectible wines. In 2008, at the annual wine charity the Napa Valley Auction, which only features Napa Valley wines, six magnums of Screaming Eagle 1992 sold for $500,000 (approximately £336,000). In 2013, the 33rd anniversary of the event, more than $16.9m was raised.